As the reliable operating temperature envelope of integrated silicon electronics has been expanded from 125° C. to temperatures above 200° C., these electronics have found beneficial use in aerospace, automotive, industrial and energy production systems. Further extension of the reliable operational envelope of semiconductor electronics above 300° C. is also expected to offer additional benefits to these industries, particularly in aerospace combustion engine applications where operating temperatures can approach or exceed 600° C. The emergence of wide band gap semiconductors including silicon carbide (SiC), diamond, and gallium nitride (GaN), has enabled short-term electrical device demonstrations at ambient temperatures from 500° C. to 650° C. However, these devices have previously not demonstrated sufficient long-term durability when electronically operated at these high temperatures to be considered viable for most envisioned applications. It is desired to provide a method for fabricating semiconductor devices that may be successfully operated continuously at temperatures of at least 500° C. for over at least 10,000 hours in air ambient with no more than a 10% change in operational transistor electrical parameters.